Photoshop: Ability to create on multiple Artboards simultaneously.

Being able to draw on multiple Artboards at once would be perfect for creatives that work on multiple designs, concepts, storyboards, thumbnails, triptychs, etc. at the same time. This allows you to visually and easily see the differences in each one, as well as how they work together as a whole. Either by the selected layers on the Artboards, all visible Artboards, or all Artboards in the document.